Not applicable.
(1) Field of the Invention
The present invention relates generally to hull-mounted sonar systems. More particularly, this invention relates to a hull-mounted system to extend the location of arrays from the hull to improve performance.
(2) Description of the Prior Art
Undersea craft, such as submarines use spherical arrays, towed arrays, and other hull-mounted arrays for sonar sensors. The size of a spherical array on a submarine is traditionally limited to roughly the diameter of the submarine""s hull. While acceptable performance levels are provided for, an increased capability for sonar detection and tracking performance is always desired, especially in the forward and rearward looking directions. Currently, the size of the array (volumetric aperture), flow noise, and blockage due to the physical location of the array on the hull, are limiting influences on sonar performance. In addition, hull-mounted sonar sensors often are subject to hull-borne vibrations and noises
Thus, in accordance with this inventive concept, a need has been recognized in the state of the art for a system for laterally extending sonar arrays from a submarine to provide significant increases in array aperture in all directions, and to fold up the arrays into grooves in the hull to reduce noise during transit.
The first object of the invention is to provide an improvement for a system for deploying and towing at least one sonar array.
Another object of the invention is to provide a system to extend sonar transducer arrays radially outwardly from a longitudinal axis of a submarine to improve its performance.
Another object of the invention is to provide a structure that extends arrays of transducers laterally from a submarine to improve performance thereof and folds along the hull to reduce noise during transit at higher speeds.
Another object of the invention is to provide an extendable, hull-mounted sonar system to increase detection, classification, and localization performance particularly in the forward and rear directions and have improved self-noise measurement.
Another object of the invention is to provide for improved detection for avoidance of mines, ocean-bottom sensing, under-ice sensing, sensing of incoming radar and laser signals, and EMI and RFI signals.
Another object of the invention is to provide for increased array gain, volumetric aperture, and hull-borne noise rejection for submarines, surface ships, weapons, and unmanned underwater and surface vehicles.
Another object of the invention is to provide a system for deploying towed arrays from and/or between each arm of deploying structure to maintain high-resolution capabilities in forward, aft, and side-looking directions.
Another object of the invention is to provide an improved system for deploying arrays using either natural, or biasing tension of the arms of the array or cables to deploy radially extendable arms.
Another object of the invention is to provide a system for deploying transducer arrays arranged in a three-dimensional umbrella-like volume.
Another object of the invention is to provide a system for deploying arrays capable of transmitting active acoustic and non-acoustic energies and detecting passive and active acoustic energy as well as non-acoustic energy at low, mid, and high frequencies, and monitoring and canceling ship/hull self-generated noise.
Another object of the invention is to provide a system for deploying arrays from a submarine at all positions from fully radially deployed to completely stowed in grooves on the hull of the submarine to provide for sensing while underway or stopped.
Another object of the invention is to provide a system for deploying arrays in deep water, shallow water, or shallow bottom depth by adjusting the extension of the structural arms.
These and other objects of the invention will become more readily apparent from the ensuing specification when taken in conjunction with the appended claims.
Accordingly, the present invention provides a system to extend at least one array from the hull of a submarine while it is in motion. A plurality of biased arms extend radially outwardly from the hull in circumferentially, nominally equal-distantly-spaced relationships from one another, and passive and/or active transducer elements of arrays are optionally mounted on the arms, trail in the water from the arms, or extend between different ones of the arms or between arms and the hull. The system of arms and transducer arrays are folded into elongate longitudinal grooves in the hull or within some other fairinglike structures on the hull to lower noise during higher speed transit by the submarine.